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PM103x Optical Power Meter Interfaces Chapter 4 Operating Instructions
In case a USB communication is established in addition to the DA-15 connection, the PM103 switches to
USB-Mode and the DA-15 serial interface becomes inactive. Only after actively closing the USB
connection, the serial communication is reestablished.
When switching the PM103 in the opposite direction, from USB to RS232 operation or to UART
operation, PM103 uses the DA-15 interface for control and output.
4.2.2.5 UART Operation
The PM103 is delivered in RS232 operation but can be switched to UART operation.
UART dependent PM103 functions:
The PM103 may need to be switched from RS232 to UART operation when using an external micro
controller for PM103 control. In RS232 operation the PM103 uses voltage levels of +/-5 V, while in UART
mode the voltage level is shifted to 0/5 V. The PM103 can also be adjusted to accommodate micro-
controllers using 3.3 V. When switched to 3.3 V, UART operation is tolerant for 5 V input signal.
For instructions on how to change the voltage level for UART operation, please refer to the document
Write-Your-Own-Applications (WYOA) for PM103x.
For UART operation, please use standard protocols for UART communication and the SCPI commands
listed in WYOA for PM103x.
4.2.2.6 RS232 Operation
The power meter PM103 can be operated with serial communication via RS232.
Please use a RS232 standard protocol for RS232 communications. For questions, please contact our
engineers at Thorlabs .
Please set up the port as follows:
115.200 Bit/s (default)
Supported range of Baud Rate: 9600 to 230400 Bit/s
LF (x0A; \n). The termination character needs to be enabled.
Note
PM103:
To operate the PM103 via RS232, RxD, TxD, and GND need to be wired from the DA-15 connector to a 9
Pin female connector to perform the connections.
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